Abstract

We have investigated the electrical and optical properties of a nBn based InAs/GaSb strained layer superlatticedetector as a function of absorber region background carrier concentration. Temperature dependent dark current, responsivity, and detectivity were measured. The device with a nonintentionally doped absorption region demonstrated the lowest dark current density with a specific detectivity at zero bias equal to at 77 K. This value decreased to at 150 K. This contrasts significantly with diodes, in which the decreases by over two orders of magnitude from 77 to 150 K, making nBn devices promising for higher operating temperatures.

Received 17 July 2009Accepted 21 August 2009Published online 24 September 2009

Acknowledgments:

The authors would like to acknowledge support from AFRL Contract No. FA9453-07-C-0171 and AFOSR Contract No. FA9550-09-1-0231. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. Department of Energy, Office of Basic Energy Sciences user facility. Sandia National Laboratories is a multiprogram laboratory operated by Sandia Corporation, a Lockheed-Martin Co., for the U.S. Department of Energy under Contract No. DE-AC04-94AL85000.